DBI

Low folate status contributes to elevated homocysteine, a metabolite that has been associated with endothelial dysfunction, arterial stiffness, and a higher risk of stroke and coronary heart disease. Large observational studies consistently show that individuals with higher homocysteine levels have greater rates of cardiovascular events, and folate intake is one of the key nutritional determinants of homocysteine. Clinically, folic acid supplementation (often combined with vitamins B6 and B12) can lower homocysteine and appears to modestly reduce stroke risk in some populations, making the identification and correction of folate deficiency an important part of broader cardiovascular risk reduction.

Folate deficiency in the periconceptional period significantly increases the risk of neural tube defects (NTDs) such as spina bifida and anencephaly, because adequate folate is required for proper closure of the embryonic neural tube in the first month of pregnancy. Large observational datasets and randomized trials have shown that appropriate folic acid supplementation before conception and in early pregnancy can reduce NTD risk by roughly 50–70% in the general population, with even greater risk reduction in women with a prior NTD‑affected pregnancy. The practical implication is that all women of childbearing potential, not just those actively planning pregnancy, are typically advised to maintain adequate daily folic acid intake so that red‑cell folate stores are sufficient well before conception occurs.

CoQ10 deficiency can present in infancy as a severe encephalomyopathy or multisystemic mitochondrial disease, with features such as hypotonia, developmental delay, intractable seizures, lactic acidosis, cardiomyopathy, and failure to thrive. Reports of infantile‑onset multisystem CoQ10 deficiency describe very early presentations, sometimes in the neonatal period, with rapid neurologic deterioration and involvement of brain, heart, kidney, and liver, and many affected children die in the first months or years of life despite intensive care. The important clinical point is that, although outcomes are often poor in the most severe cases, some infants and young children show neurologic improvement or stabilization when CoQ10 deficiency is recognized early and high‑dose CoQ10 supplementation is started promptly, which is why this diagnosis is considered a treatable cause of infantile encephalomyopathy

CoQ10 is a key mitochondrial antioxidant, and circulating levels are often reduced in people with chronic kidney disease and chronic heart failure, where deficiency is linked to greater oxidative stress and poorer organ function. In CKD cohorts, lower CoQ10 levels correlate with increased cardiovascular risk, and supplementation has been reported to improve markers such as proteinuria, mitochondrial function, and oxidative stress, with some studies suggesting better preservation of kidney function over time. In patients with chronic heart failure, trials such as Q-SYMBIO have shown that CoQ10 supplementation can improve cardiac function parameters and significantly reduce major adverse cardiovascular events, cardiovascular mortality, and heart‑failure–related hospitalizations.

In older adults, low folate status has been associated with a higher risk of mild cognitive impairment (MCI) and faster cognitive decline over time, likely through effects on one‑carbon metabolism and homocysteine. Several longitudinal cohort studies have found that individuals with lower serum or red‑cell folate and higher homocysteine show steeper declines on memory and global cognition tests, and in some cohorts have a significantly higher incidence of MCI or dementia over follow‑up. The clinically important takeaway is that, when folate deficiency is detected and corrected (usually along with ensuring adequate vitamin B12), some patients demonstrate stabilization or modest improvement in cognitive performance, particularly when interventions are combined with aggressive management of vascular risk factors such as hypertension and diabetes.

CoQ10 deficiency has been identified as a potentially reversible cause of steroid‑resistant nephrotic syndrome and glomerular nephropathy, particularly in children and young adults with genetic defects in CoQ10 biosynthesis. In reported series, affected patients often present with heavy proteinuria and progressive kidney dysfunction that fail to respond to standard steroid therapy, but genetic testing sometimes reveals mutations in CoQ10‑related genes (such as COQ2, COQ6, or ADCK4). The encouraging part is that in a subset of these cases, early and sufficiently dosed CoQ10 supplementation has been associated with reduced proteinuria and stabilization or partial improvement of kidney function, making it an important, treatable consideration in otherwise unexplained steroid‑resistant nephrotic syndrome.